Impact of metabolic syndrome on the outcomes of percutaneous renal angioplasty and stenting

Background

Endovascular therapy for symptomatic atherosclerotic renal artery stenosis (ARAS) is common and effective in the well-selected patient. Hypertension is a common indication for intervention and a major component of metabolic syndrome (MetS). The impact of MetS on outcomes after percutaneous renal intervention is unknown.

Methods

We performed a retrospective analysis of records from patients who underwent endovascular intervention for ARAS and were followed by duplex ultrasound between January 1990 and January 2008. MetS was defined as the presence of ≥3 of the following criteria: Blood pressure ≥140 mm Hg/≥90 mm Hg; triglycerides ≥150 mg/dL; high-density lipoprotein ≤50 mg/dL for women and ≤40 mg/dL for men; fasting blood glucose ≥110 mg/dL; or body mass index ≥30 kg/m². The average follow-up period was 3.3 years. Clinical benefit defined as freedom from renal-related morbidity (increase in persistent creatinine >20% of baseline, progression to hemodialysis, death from renal-related causes) or freedom from recurrent hypertension, anatomic patency, restenosis, and patient survival were measured.

Results

Five hundred ninety-two renal artery interventions were performed in 427 patients. Fifty-two percent were identified as having MetS. Patients with MetS were more often female (35% vs 50%, NoMetS vs MetS). There were no significant differences in presenting symptoms. There was no peri-operative mortality and equivalent morbidity (6% vs 7%, NoMetS vs MetS). Patients with MetS had equivalent survival and cumulative patency. However, the MetS group had a lower five-year freedom from restenosis (87±2% vs 69±9%, NoMetS vs MetS; P < .01) and lower five-year retained clinical benefit (71±8% vs 45±8%, NoMetS vs MetS; P < .01) with a higher number progressing to hemodialysis (3% vs 13%, NoMetS vs MetS; P < .01). Individually, the components of MetS did not influence outcomes. Statin therapy did not influence outcomes.

Conclusion

MetS is associated with markedly reduced renal clinical benefit and increased progression to hemodialysis following endovascular intervention for atherosclerotic renal artery stenosis. MetS is thus a risk factor for poor long-term outcomes following renal interventions.